Learn Turkish: Öğrenci kalemliğini okulda unuttu. - The student forgot his pencil case at school.

The root is kalem (pen or pencil). The suffix -lik (which follows 4-way vowel harmony) is often used to create nouns that mean a container or a place for something. Adding it to kalem creates kalemlik, meaning pencil case.

Why is there a ğ in kalemliğini instead of a k?

The base word for pencil case is kalemlik. When we add a suffix starting with a vowel, such as the possessive suffix -i (his/her), the hard k at the end softens to a ğ. This is a standard consonant mutation. So, kalemlik + -i becomes kalemliği.

What are the extra letters at the very end of kalemliğini?

After forming kalemliği (his pencil case), we need to show that it is the specific direct object being forgotten. We do this by adding the accusative case suffix -i. Because you cannot attach this directly to a possessive suffix ending in a vowel, you must use the buffer letter -n-. That gives us kalemliği + n + i = kalemliğini.

The English translation says 'his pencil case', but where is the word for 'his'?